SSRL Science Highlights Archive

Approximately 1,600 scientists visit SSRL annually to conduct experiments in broad disciplines including life sciences, materials, environmental science, and accelerator physics. Science highlights featured here and in our monthly newsletter, Headlines, increase the visibility of user science as well as the important contribution of SSRL in facilitating basic and applied scientific research. Many of these scientific highlights have been included in reports to funding agencies and have been picked up by other media. Users are strongly encouraged to contact us when exciting results are about to be published. We can work with users and the SLAC Office of Communication to develop the story and to communicate user research findings to a much broader audience. Visit SSRL Publications for a list of the hundreds of SSRL-related scientific papers published annually. Contact us to add your most recent publications to this collection.

Diatoms, single-celled marine algae that create beautiful, symmetric cell walls composed of silica, are critical to ocean ecosystems. Responsible for up to 20% of photosynthesis in oceans, these phytoplankton are also an important part of Earth’s carbon cycles. The potential of diatoms and other phytoplankton to sequester atmospheric CO2 has led to geoengineering ideas like “iron fertilization” of oceans.

Molecular hydrogen (H2) is a promising carrier of energy for a future that uses more sustainable sources of fuel. H2 created from splitting H2O using renewable energy methods could result in no carbon footprint energy use. While methods of water splitting are being developed, reverse reactions are a problem.

Amrita Bhattacharyya, Colorado State University, Thomas Borch, Colorado State University

The radioactive element uranium is well-known for its role in nuclear energy. People mine naturally occurring uranium from deep sandstone deposits called roll fronts. Scientists have long thought that abiotic chemical reactions that occur over millions of years resulted in formation of crystalline uranium. An international team of scientists has challenged this basic theory, finding evidence for a different genesis for uranium in roll front deposits.

While scientists recognize that oxygen-free soil stores large amounts of carbon, knowledge about the processes that protect and preserve carbon-rich molecules in these environments is lacking. In oxygen-rich soil, microbes break down organic molecules through aerobic respiration, allowing carbon to escape the ground as carbon dioxide gas.

Emmanuel Skordalakes, The Wistar Institute, University of Pennsylvania

Famous for their role in the process of aging, telomeres are the regions of repetitive DNA sequences at the ends of our chromosomes. These repeats are critical for preserving the structure and function of our DNA in concert with numerous cellular factors. One factor responsible for the regulation and maintenance of telomere length is the shelterin complex, composed of six proteins including one called POT1.

An intracerebral hemorrhage (ICH) stroke occurs when a blood vessel bursts inside the brain and blood leaks into brain tissue. Secondary damage is caused by hemoglobin iron making free radicals that cause oxidative damage to brain cells. While prompt rehabilitative therapies have been shown to limit damage, the mechanism for this is unknown.

David Buchwalter, North Carolina State University, Dean Hesterberg, North Carolina State University

Coal-ash spills in Tennessee and North Carolina rivers have prompted concerns that toxic trace elements like arsenic could be concentrated in the food web to potentially affect humans. At the base of these freshwater food webs are periphyton biofilms, which contain a complex ecosystem of micro-organisms including bacteria, fungi, diatoms, and algae. Such biofilms can concentrate trace elements hundreds to thousands of times. To investigate whether arsenic concentrated in biofilms is propagated up the food chain, a team of scientists has studied the bioavailability of arsenic to organisms that feed on the periphyton biofilms.

Microtubules (MTs) are sub-cellular structures made of the protein tubulin. They have important roles in moving organelles around the cell and in chromosome segregation before cell division. MTs can exist in two states, either a dynamic state of growing and shrinking MTs or a stable state. MTs can also form complex bundles that can be found in neuronal axons. The neuronal protein Tau helps facilitate this process and has been implicated in some neurodegenerative disorders like Alzheimer’s disease. Yet Tau’s exact role in MT formation and bundling is unclear: different experiments (both in vivo and cell free) have shown Tau to mediate either attractive or repulsive forces between MTs.

The presence of the receptor tyrosine kinase Axl on tumor cells is correlated with disease severity and thus is an important oncology target. Developing inhibitors to Axl has been met with limited success due to the tight affinity with which Axl binds its ligand, growth arrest-specific 6 (Gas6). Researchers have engineered a soluble “receptor decoy,” called MYD1, based on Axl’s ligand-binding domain, that binds Gas6 even more tightly than Axl does.